Part 3
Plan, Houses and Power Plants
Chapter 1 Plan
Article 36. Hygienic condition for plan, house and powerhouse plant)
Condition of the following items must be inspected and checked periodicallyduring operation period in order to keep hygienic condition of plan, houses and works for smooth operation of a power plant.
1.Surface and underground drainage system for the whole plan of power plant, substation and relevant facilities;
2.Dust precipitating system and ventilating system;
3.Waste water treatment systems;
4.Water supply system and drainage system;
5.Sources for domestic water, reservoirs and protecting system for water sources;
6.Railways and roads in yards of power plant, substation and relevant facilities;
7.Fences, illumination for parks, other cultural works and public works;
8.Systems for monitoring underground water level.
9.Lighting system of power plant, substation and relevant facilities.
In case that the inconformity with the requirements in relevant environmental regulations are detected in the inspection and checking, necessary measuresmust be taken immediately toimprove the condition.
Article 37. Protection of water route, gas pipeline and cable route
In order to make visible for embedded subjects such as underground water pipes for water supply and wastewater system, embedded gas pipelines and cables, clear and solid displaymust be provided for such subjects in a systematic manner.
Photo 37-1 Sample of indication pile
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Article 38. Water treatment
1.When the wastewater contains pollutant such as oil and chemicals, water treatment system is required before releasing such polluted wastewater into a natural river or reservoir or sea.
In order to avoid violation against industrial hygiene regulations, it is required to check the quality of wastewater periodically.
It shall be referred to Article 228 of this Guideline regarding water treatment of thermal power plant.
2.Power house Water Treatment and Drainage System
1) General arrangement of the water treatment and drainagesystem for the station is shown on the Figure 38-1 Powerhouse-Waste Water Disposal System in Hydro-power Plant.
Figure 38-1 Powerhouse-Waste Water Disposal System in Hydro-power Plant
2) In the absence of anypossibility to drain water naturally by gravity from thePowerhouse, there is a vital need to provide a powerful and reliable pumped drainage system.
3)Water to be pumped from the Station must be classified as followed;
(1)Seepage water through civil construction works,
(2)Seepage water from auxiliary mechanical equipment, hydro-mechanical equipment under normal operation in the even of emergency such as through the break of an auxiliary pressure pipe and other drainage sources originating from the process,
(3)Seepage water through turbine shaft and head cover,
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(4)Water source after fire fighting.
4)Except the water seeped through civil construction works and the water in the unit waterway, which are considered as natural sources without oil contamination and to be directly discharged to the river, the other sources of water are potentially oil contaminated and must be treated by separating oil and water before being discharged to the river.
(Refer to Vol.4, Part 4, Chapter 4, Article 91 Oil treatment)
a.QCVN 14:2008/BTNMT – National Technical regulations on domestic waste water
b.QCVN 24:2009/BTNMT National Technical regulations on industrial waste water
c.QCVN 38:2011/BTNMT – National Technical regulations on quality of surface water to protection aquatic lives
d.QCVN 39:2011/BTNMT – National Technical regulations on water quality for irrigated agriculture
e.Decision No. 23/2006/QĐ-BTNMT – Listing hazardous substances
f.Circular No. 47/2011-TT-BTNMT – National Technical regulations on environment
Article 39. Stability of plan
In case that the settlement, landslide and fracture are detected on the plan, proper measuresmust be carried out to eliminate or mitigate causes of the above-mentioned phenomena in order to prevent the power plant facilities or network facilities from damages.
In order to prevent the plan from settlement, landslide and fracture, routine inspectionmust be conducted for monitoring of land condition and groundwater level by providing monitoring points at potential locations where such failure in land condition may occur.
Article 40. Railway and road
Railways and relevant works located in the yard and the area derun the control of the power plant must be managed and maintained in line with regulations of railwayssuch as Railway Traffic Law (No. 35/2005/QH11). In addition, other relevant regulations shall refer to Article 105 of this Guideline. Management and maintenance of roads in the same area must be also in accordance with the technical regulations and standards of transport and communication sectorssuch as Road Traffic Law (No. 23/2008/QH12).
In addition, railways and roads must be arranged and maintained to be convenient for maintenance work and for access to adjacent facilities and to secure safety conditions for pedestrians and vehicles.
Chapter 2 Houses, Power Plant, Technical and Hygienic
Equipment
Article 41. Principles in maintenance
Power plants and relevant facilities, houses and related structuresmut be maintained in good condition, and secured for durable, stable and reliable operation of power plants and network facilities as designed.
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In addition, they must satisfy occupational safetyrequirements and industrial hygiene requirements for staffs working at power plants and network facilities.
Article 42. Routine and emergency Inspection of houses, works and equipment
The owner must monitor the condition of houses, worksincluding ancillary facilities and equipment to secure reliable operation of power plants and network facilities, and check them comprehensively to detect damages, deteriorationsand potential failure periodicallyas routine inspection activities in daily maintenance work.
In case that the breakdown or natural hazards such as fire, earthquakes, heavy storm and flood would happen at the area where electrical facilities and equipment are installed, preparation against such hazard must be carefully made and, once such hazard occurred, emergency inspection must be carried out immediately after the incidents in order to detect the damages and take proper measures for securing safety of houses, works and equipment..
Article 43. Check of houses and works on particular ground
In addition to |
the provision in Article 42,t iis necessary to take particular care forthe |
condition |
of |
houses and |
works constructed at new earth-filled area, settlement area and the |
location |
where |
vibration appears frequently during operation by checking carefully and continually. |
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Article 44. Check of durability of houses and works
When keeping a close watch is required on durability of houses and works, it is necessary to check the condition of following items of house and works:
-Supporting column (crack, deformation, etc.)
-Expansion gaps (width of gap)
-Welded seams (crack, deformation, abrasion, rust, etc.)
-Joints (loosening, etc.)
-Structures of reinforced concrete (crack, deterioration, settlement, etc.)
-Structures and parts affected by active load and heat (damages, deformation, etc.)
It is required for the above items to be checked periodically and continuously to detect the changes in condition or progress of unfavorable phenomena.
Article 45. Countermeasures for fractures and damages
In case that fractures or damages on structures are detectedon houses or works, subsequent actions must be selected carefully according to the degree, location and causes of fractures and damages. Excluding the cases that defects are structurally and functionally negligible or, on the contrary, urgent repair works are required immediately, careful successive inspection must be carried out for detected fractures or damages. Depending on the conditions of defects, proper monitoring equipment such as plumb lines, crack gauges, displacement meters, etc. must be installed immediatelyfor accurate monitoring.
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A series of investigationactivities correctly in order to utilize such causes of defects.
and countermeasures taken for the defectsmust be recorded records formaking proper maintenance plan in due considering
Article 46. Check of chimney (deleted)
Article 47. Alteration of facilities
It is prohibited in principle to alter loading condition on facilities by applying additional load such as piercing, arranging heavy machinery and materials,or installing ducts and pipelines, which may damage the stability and safety of facilities.
Overload or alteration must be permitted only on the condition that the safety would be confirmed by design calculation. If alteration of loading condition isneeded, such structuresmust be reinforced properly based on the design calculation.
It is necessary to arrange instruction boards indicating the allowable limit load at visible place on each section of floor surface in order to easily recognize allowable limit-load.
Article 48. Corrosion protection of metal structures
Power plant staff must check metal structure of houses at daily patrol and inspection and must confirm status of it because it is corroded and damaged as time goes by. Points to be checked on daily patrol and inspection of houses are shown as follows;
1.Inspection must be conducted for houses according to procedures developed by each power plant.
2.The following places must be checked mainly because metal structures in these places are easy to corrode.
1)Places damaged from salt
2)Blowy places
3)Humid places
4)Places damaged from rainwater
3.The following equipments and parts must be checked mainly because these equipments are easy to corrode.
1)Pipe rack
2)Bolts and nuts
3)Welded parts
4)Joint parts
5)Painting parts (peeling)
4.Corroded parts must be changed to new parts or corrosion must be removed by grinder and repainted when finding corrosion on above equipments and parts.
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